1, 3, 7, 9-tetramethyl-2, 4, 6, 8-tetraoxodipyrimido [4.5-b, 5&#39;.4&#39;-e] pyrazine



Patented July 24, 1951 UNITED STATES ATENT OFFICE Oliver De Garmo, St.Louis, Mo., assignor to Monsanto Chemical Company, St. Louis, Mo., acor-.

poration of Delaware No Drawing. Application May s, 1950,

Serial No. 160,820

0 t1 II The novel compound of this invention may be convenientlyprepared by reacting 1,3-dimethyl- 4,5-diamino uracil with dimethylalloxan. Preferably, the reaction is carried out by reactingapproximately equimolecular proportions of the aforementioned reactantsin an aqueous alkaline medium, such as a water solution of an alkalimetal hydroxide or carbonate, at a temperature in the range of fromabout 0 C. to about 100 C. The following example is illustrative of amethod of preparing the novel compound of this invention:

9.4 parts by weight of dimethyl alloxan and 8.5 parts by weight of1,3-dimethyl-4,5-diamino uracil were added to 500 parts by weight ofwater. The mixture was heated to a temperature in the range of about-100 C. and maintained at a temperature in that range for a period ofabout five hours with continuous stirring. parts by weight of N/2 NaOI-Iwere then added and, after an additional two hour heating period, theprecipitate of1,3,7,9-tetramethyl-2,4,6,8-tetraoxodipyrimido[4.5-b,5'.4'e]pyrazine,which had formed in the reaction mixture, filtered from the hot 60-100C.) reaction mixture. The precipitate was washed with cold water anddried at a temperature of about C. The dried material was recrystallizedfrom ethyl alcohol.

The substantially pure l,3,7,9-tetramethy1- 2,4,6,8-tetraoxodipyrimido[4.5-b,5".4'-e] pyrazine thus obtained was a light yellow crystallinesolid having a melting point of 206.0-207.0 C.

What is claimed is:

1. 1,3,7,9-tetramethyl-2,4,6,8-tetraoxodipyrimido[4.5-b,5'.4-e]pyrazine.

2. The process of preparing 1,3,7,9-tetramethyl-2,4,6,8-tetraoxodipyrimido [4,5-b,5' .4-e]=p-yrazine, which comprisesreacting l,3-dimethyl-4,5-diamino uracil with dimethyl alloxan.

3. The process of preparing 1,3,7,9-tetramethyl-2,4,6,8-tetraoxodipyrimido [4 .5 -b,5-' .4 -elpyrazine, which comprisesreacting approximately equimolecular proportions of1,3-dimethyl-4,5-diamino uracil and dimethyl alloxan in an aqueousalkaline medium.

OLIVER DE GARMO.

No references cited.

1.1,3,7,9-TETRAMETHYL-2,4,6,8-TETRAOXODIPYRIMIDO(4.5-B,5''.4''-E)PYRAZINE.